A backcountry area in general terms is a geographical region that is:

• isolated
• remote
• undeveloped
• difficult to access

The term particularly applies to mountainous regions that are reasonably close to urban areas but are:

• not immediately accessible by road
• at relatively high altitude
• not frequented by human visitors

While the term "backcountry" is roughly comparable to the term "wilderness", they are not necessarily equivalent. "Wilderness" implies more the state whereas "backcountry" implies more the position. Backcountry is similar to hinterland.

Wilderness areas | Geography (terminology)